Package org.anchoranalysis.core.identifier.provider.store

Class LazyEvaluationStore<T>

Object

LazyEvaluationStore<T>

Type Parameters:

T - item-type in the store

All Implemented Interfaces:

NamedProvider<T>, NamedProviderStore<T>

public class LazyEvaluationStore<T>
extends Object
implements NamedProviderStore<T>

Lazily delays evaluating items until when they are first retrieved.

The StoreSupplier is called only upon first retieval, and thereafter stored.

Author:

Owen Feehan

Constructor Summary

Constructors

Constructor	Description
LazyEvaluationStore(String storeDisplayName)	Creates a new LazyEvaluationStore instance.

Method Summary

Modifier and Type	Method	Description
void	add(String identifier, StoreSupplier<T> supplier)	Adds an element to the store.
T	getException(String key)	Retrieves the item if it exists, or throws an exception if it doesn't exist.
Optional<T>	getOptional(String key)	Retrieves the item if it exists, or returns Optional.empty() if it doesn't exist.
Set<String>	keys()	Returns a set of keys associated with the provider.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.anchoranalysis.core.identifier.provider.NamedProvider

getArbitraryElement, isEmpty

Constructor Details

LazyEvaluationStore

public LazyEvaluationStore(String storeDisplayName)

Creates a new LazyEvaluationStore instance.

Parameters:

storeDisplayName - A user-friendly name to describe the store, when printing its contents in a string-representation.

Method Details

getException

public T getException(String key)
               throws NamedProviderGetException

Description copied from interface: NamedProvider

Retrieves the item if it exists, or throws an exception if it doesn't exist.

Specified by:

getException in interface NamedProvider<T>

Parameters:

key - a unique name for the item.

Returns:

the item

Throws:

NamedProviderGetException - if no item exists for identifier

getOptional

public Optional<T> getOptional(String key)
                        throws NamedProviderGetException

Description copied from interface: NamedProvider

Retrieves the item if it exists, or returns Optional.empty() if it doesn't exist.

Note that a 'key' might still throw an exception for another reason (but never because a particular key is absent).

Specified by:

getOptional in interface NamedProvider<T>

Parameters:

key - a unique name for the item.

Returns:

the item, if it exists, otherwise Optional.empty().

Throws:

NamedProviderGetException - if no item exists for identifier.

keys

public Set<String> keys()

Description copied from interface: NamedProvider

Returns a set of keys associated with the provider.

There's no guarantee that it refers to all valid keys.

Specified by:

keys in interface NamedProvider<T>

Returns:

a set of all keys associated with the provider.

add

public void add(String identifier,
 StoreSupplier<T> supplier)
         throws OperationFailedException

Description copied from interface: NamedProviderStore

Adds an element to the store.

Specified by:

add in interface NamedProviderStore<T>

Parameters:

identifier - a unique identifier for the element.

supplier - supplies the element to be added (which may be evaluated immediately, or a later point lazily).

Throws:

OperationFailedException - if the identifier already exists, or otherwise the add operation fails.